Synergists to aerosol insecticides



' sion of 'ag'ents which will Patented Apr. 4, 1944 2,345,909 SYNERGISTS TO AEROSOL INSECTICIDES William N. Sullivan,

Washington, D. 0., and Lyle D. Goodhue, Berwyn, Md., assignors to the United States of America Claude R. Wickard, Secretary 01' Agriculture, and his successors in office No Drawing. Original application September 30,

1941, Serial No. 412,960. application January 7, 1944,

Divided and this Serial No. 517,376

3 Claims. (01. 167-22) (Granted under the act of March 3, 1883, as

amended April 30, 1928; 370

This application is made under the act of March 3, 1883, as amended by the act 01' April 30, 1928, and the invention herein described and claimed, ii. patented, may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment to us of any royalty thereon.

This is a division of our 'copending application or patent, Serial No. 412,960, filed September 30, 1941.

Our invention relates to materials which will increase the eflectiveness of insecticides in aerosol form.

Certain agents which may or may not be toxic in themselves when added to aerosol insecticides greatly increase the rate of mortality. The increased toxicity obtained by the combination of such materials is often referred to as "synergism" and the added material a synergist." Therefore, in these terms, the general object of our invention is the provision of materials suitable as synergists for aerosol insecticides.

Another object of our invention is the provinot only increase the insecticidal action of materials known to possess some toxicity, but, which will also impart insecticidal properties to materials which are known to be non-toxic or to have a very low toxicity.

A further object of our invention is the provision of such agents acting as synergists, which can be applied by dispersion simultaneously with and by the same methods used for the preparation of aerosol insecticides.

We have found that materials suitable for the purposes of this invention belong most frequently to the class of chemical compounds which are surface active in non-aqueous solvents or'which act as detergents in non-aqueous solvents. These componnds, in general, contain polar groupings such as the hydroxyl, the carboxyl, the amine, the ammonium, or the sulfonic acid, alone, in multiple, or in combination, which is attached to some long chain aliphatic radical, or, in some cases, an aromatic radical.

Substances acting as detergents or surface active agents in non-aqueous media can be easily applied by the usual methods of aerosol production, but this invention is not limited to these v that the mere wetting of the substances because diiierent methods of aerosol production can be many processes which to apply these materials in the form of aerosols, such as spraying into the atmosphere, vaporizasynergist and the insecticide.

A synergist to an insecticide in aerosol form is not necessarily also a synergist to an insecticide in spray form, even of the same compound. Actual tests have disclosed that an agent which possesses little or no efiect as a synergist to an insecticidal spray may be extremely eflective as a synergist to an insecticidal aerosol. The reason for this is not apparent, but it would seem insect cannot ex plain the action.

The following results were obtained using synergists in accordance with this invention. These results were obtained on the basis of preliminary tests first carried out in a small chamber of 7 cu. ft. and then on a larger scale in a 216 cu. ft. chamber. In each test from 500 to 600 flies were used. Six-tenths of a pound of o-dichlorobenzene per 1000 cu. it. gave only a 2% kill. However, when mixed with 0.16 lb. of oleic acid as a synergist, a kill was obtained. This same obtained.

The same simereists were tested at other concan be used lauric acid was also found to be efiective and vice centrations and it was found that llttle'is gained by adding more than 10%.

The following is a list of substances which were tested as synergists at a concentration of 0.06 lb. in 0.6 lb. of c-dichlorobenzene per 1000 cu. it. against the housefly, the percentage oi kill in each case being indicated in the right hand column:

Per cent kill Spermaceti Diglycol laurate 48 Sulfonated naphthalene 60 Salicylic acid 91 Propylene glycol oieate 2'8 Myristic acid 49 Propylene glycol laurate.. 74 Sorbitol laurate 59 Monoglycol iaurat 56 Triethanolamine oleate-..*. 56 Lauryl sulfa '70 Other insecticides were used against the American and German cockroach at a concentration of.

1.5 lbs. per 1000 cu. ft. One-tenth of the insecticide was replaced by a synergist. A mortality of 100% was obtained with the following: methyl chioroacetate plus lauric acid, epichlorohydrin plus lauric acid, epichlorohydrin plus oieic acid, ethyl dlchloroacetate plus lauric acid, ethyl dichloroacetate plus oleic acid, beta-chloroethyl chlorocarbonate plus lauric acid, beta-chloroethyiacetate plus lauric acid, tetrachloroethane plus lauric acid, and o-dichlorobenzene plus lauric acid. In all cases where oleic acid was efiective,

versa. The kill without a synergist was always less than 100% and usually less than 50%.

In a 1100 cu. ft. room, naturally infested with cockroaches, more than 5000 were killed in 18 hours and none were found living, using 1% lbs. of o-dichlorobenzene with 3% lauric acid and 2% oleic acid. Excellent results were also obtained in a 3200 cu. ft. room.

10 Tests were also conducted against the carpet beetle larva, the confused flour beetles and crickets. The halogenated esters in combination with any one of the synergists mentioned above are extremely toxic to the confused flour beetle and 15 produce a high mortality to the carpet beetle larva.

Among 80 compounds tested against the housefly in the form of aerosols, in combination with synergists of the type mentioned above, are 3-- 2o chloroacenaphthene, 2-chlorofluorene, 3-chlorodibenzofuran, chlorinated diphenyls, halogenated naphthalenes, halogenated esters, halogenated ketones, carbazole, thiocresol and halogenated phenols. The synergist was shown to be respon- 25 sible in each case for an increase in toxicity.

Having thus described our invention, we claim:

1. An insecticide in aerosol form comprising lauric acid and 3-chloroacenaphthene.

2. An insecticide in aerosol form comprising 30 lauric acid and 2-chlorofiuorene.

3. An insecticide in aerosol form comprising lauric acid and 3-chlorodibenzofuran.

WILLIAM N. SULLIVAN. LYLE D. GOODHUE. 

